We present the first measurement of the reaction gamma p -> a(2) (1320)(0) p in the photon energy range 3.5-5.5 GeV and four-momentum transfer squared 0.2 < -t < 2.0 GeV2. Data were collected with the CEBAF Large Acceptance Spectrometer detector at the Thomas Jefferson National Accelerator Facility. The a(2) resonance was detected by measuring the reaction gamma p -> pi(0)eta p Tip and reconstructing the pi(0)eta invariant mass. The most prominent feature of the differential cross section is a dip at -t approximate to 0.55 GeV2. This can be described in the framework of Regge phenomenology, where the exchange degeneracy hypothesis predicts a zero in the reaction amplitude for this value of the four-momentum transfer.
Celentano, A., Battaglieri, M., De Vita, R., Marsicano, L., Mathieu, V., Pilloni, A., et al. (2020). First measurement of direct photoproduction of the a2(1320)0 meson on the proton. PHYSICAL REVIEW C, 102(3), 032201 [10.1103/PhysRevC.102.032201].
First measurement of direct photoproduction of the a2(1320)0 meson on the proton
D'Angelo A.Membro del Collaboration Group
;Lanza L.;Rizzo A.Membro del Collaboration Group
;
2020-09-28
Abstract
We present the first measurement of the reaction gamma p -> a(2) (1320)(0) p in the photon energy range 3.5-5.5 GeV and four-momentum transfer squared 0.2 < -t < 2.0 GeV2. Data were collected with the CEBAF Large Acceptance Spectrometer detector at the Thomas Jefferson National Accelerator Facility. The a(2) resonance was detected by measuring the reaction gamma p -> pi(0)eta p Tip and reconstructing the pi(0)eta invariant mass. The most prominent feature of the differential cross section is a dip at -t approximate to 0.55 GeV2. This can be described in the framework of Regge phenomenology, where the exchange degeneracy hypothesis predicts a zero in the reaction amplitude for this value of the four-momentum transfer.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
